I would bring…

a magic atlas to warn you about the deadly dangers ahead between you and the treasure,

a pair of teleportation boots to make your journey easy,

a pack that contains a feast fit for a king that will never run out,

a cape made from a scaly dragon hide to protect you,

a magical pendant crafted from the most skillful faries to guide you when you are lost,

a magical sword that points to which part of the beast you should slay

and an alpha male wolf that will only be most loyal to you and carry magical powers like saliva acid.